Burglar-alarm



(No Model.)

- A. JACOBI.

BURGLAR ALARM. No. 314,450. PatentedMar. 24, 1885.

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ALEXANDER JACOBI, OF ST. CLAIR, MICHIGAN.

BURGLAR-ALARIVI.

SPECIFECATION forming part of Letters PatentNo. 314,450, dated March 241885.

Appicaton tiled October 22, 1884. (No model.)

To all whom may concern:

Be it known that I, ALEXANDER JaooBr, of St. Clair, in the county of St.Clair and State of Michigan, have invented new and useful Improvementsin BurglarAlarms; and I do hereby declare that the following is a full,clear, and eXact description thereof, reference being had to theaccompanying drawings, which form a part of this speciticationl Thisinvention relates to certain new and useful improvements inburglar-alarms; and the invention consists in the peculiar combinationsand the construction and arrangement of parts, all as more fullyhereinafter set forth and claimed.

Figure l is a sectional elevation showing the manner of connectionbetween the detent and the hammer of the alarm. Fig. 2 is an elevationshowing the manner ot' connecting the device to doors and windows. Fig.3 shows manner of attaching to door in detail.

In the accompanying` drawings, which form a part of this specification,A represents a suitable base, to which is secured a case, B,

to receive the spring-alarm C, of any ot' the known constructions, andprovided with a hammer, D, arranged to ring the bell E upon the releaseof the hammer, as hereinafter specified.

N is an arm secured to the hammer rod, as shown, the free end of sucharm being provided with an eye, a, designed. when the device is set foruse, to come between the two staples b projecting from the base A.

M is a detent, the lower end ot' which passes through the staples b andthe eyes a, and is provided with any suitable tension devicesuch as thespring F-to prevent the too easy withdrawal of the detent and to keepthe alarmcord O properly stretched. The main alarm= cord O is secured atone end to the upper end of the detent M, while its opposite end may beattached to the door or window farthest from the alarm in such a mannerthat when such door is opened the alarm-cord will be drawn upon, therebywithdrawing the detent from its engagement with the arm N of the hammer,allowing the clock-work to operate the hammer and ring the bell.

At windows and doors intermediately situated may be employedsupplemental alarmcords P, one end of which should be connected to themain alarm-cord O, with the opposite end connected to the door or windowin such a manner that when either a door or window is opened the detentwill be disengaged, as abovedescribed, and set the alarm off.

A hook, G, may be employed to engage with the hammer D so as to preventthe hammer from operating, even should the detent be disengaged. In thiscasethe windows and doors can be opened at will through the day-timewit-hout disengagin g the alarm-cords; but care should be taken at nightto release the hammer-arm and place the detentin its proper position.

I am aware of the Patents Nos. 201,382, 206,105, and 258,458, and makeno claim to the construction shown thereby, but limit myself to theexact construction lherein shown and described.

By my construction I dispense with the complicated devices heretoforeemployed in this class of alarms without detriment to perfeet working ofthe device.

The construction is simple, inexpensive as compared with Apreviousdevices of this kind, is positive in its action, and less liable to getout of order.

Vhat I claim as my invention is- In an auto-mechanical burglar-alarm,the combination, with the base A and case B, provided with sp ring-alarmC and hammer D, of the arm N, secured to the hammer-rod and providedwith the eye a., the staples b, projecting from said base, the detent M,the lower end of which passes loosely through said eye a and staples b,and the frictional tensionspring F bearing on the side of said detent, amain cord, O, attached to said detent and passing to the window or doorfarthest therefrom, and the branch cords l?, connecting said main cordwith the other windows and doors of the building, whereby the opening ofa door or window withdraws said detent from said eye a and staples b,substantially as and for the purpose specilied.

ALEXANDER JACOBI.

Witnesses:

H. S. SPRAGUE, CHARLES J. HUNT.

